Keystone ( - ) is a painter. Keystone s works have been put up for auction numerous times, with realized prices varying from 154.98 USD for „Sturm über dem Ozean“ (Storm at sea) circa 1930 in 2005 to 464.94 USD for John Cobb in Napier racing car, 1937 in 2005 , based on the size and medium of the artwork.